The expression levels of IL-4 and IL-13 in the serum and blister fluid of patients with bullous pemphigoid

Abstract

Objective To investigate the expression levels of type 2 inflammatory cytokines, IL-4 and IL-13, in the serum and blister fluid of patients with bullous pemphigoid (BP). Methods The serum or blister fluid was collected from BP patients (49 cases) and healthy individuals (33 cases). ELISA was used to measure the concentrations of IL-4 and IL-13. The expression levels of IL-4 and IL-13 were compared between the BP patients and healthy controls. The correlations of IL-4 and IL-13 with total serum IgE levels, eosinophils, skin erythema score and pruritus severity (NRS) in BP patients were analyzed. Moreover, the associations of BP180 and BP230 IgG antibodies with IL-4, IL-13 and total serum IgE levels, and eosinophils were determined. Results The concentrations of IL-4 and IL-13 in the blister fluid, but not in the serum, were significantly higher in the BP patients than in the healthy controls (P<0.01). Serum levels of either IL-4 or IL-13 were not significantly correlated with total serum IgE levels, eosinophils, erythema score and NRS in BP patients. However, IL-4 levels in blister fluid were positively correlated with total serum IgE levels in BP patients (r=0.98, P=0.021). The IL-13 levels in blister fluid were associated with serum BP180 positive, but BP230 negative (r=0.58, P=0.009). Conclusions Elevated IL-4 and IL-13 levels in the involved skin site of bullous pemphigoid suggest the present of local type 2 inflammation. Total IgE levels may reflect the severity of local type 2 inflammation. BP180 complex may affect the development of type 2 inflammation through increasing local IL-13 levels. These findings might be helpful in the target therapy in the future.

Keywords

• bullous pemphigoid
• type 2 inflammation
• il-4
• il-13
• eosinophils